In order to provide the necessary stability for cranes and similar equipment during work operations, the wheeled frame of the crane is typically provided with stabilizing outriggers. Outriggers are usually provided on laterally opposite sides of the equipment frame, with a pair of outriggers typically provided at each end of the frame. Each outrigger is adapted to engage the ground outwardly of the frame so that the stance of the crane is significantly wider during work operations. In this way, a significantly greater degree of stability for the frame is afforded than when the frame is being supported by its wheels.
Because the widest possible stance of the outriggers provides the best stability, it is desirable that the outriggers be extensible to positions outwardly of the equipment frame as much as possible. On the other hand, however, it is further desirable for the overall width of the crane to be as narrow as possible when the outriggers are not extended for enhancing the ease of maneuverability and transport of the crane, and for compliance with regulations prescribing certain maximum widths for transport purposes.
To this end, various arrangements are known in the art for articulation of the outriggers between stowed and extended positions. Some of these arrangements, such as shown in U.S. Pat. No. 3,426,918, to Keinonen, include a laterally shiftable outrigger including a pivotal leg portion, while others, such as shown in U.S. Pat. No. 3,337,063, to Testore, include linkage arrangements for movement of the outriggers inwardly and outwardly of the equipment frame. While outrigger support arrangements of these types are effective in providing the desired stance for the crane during work operations while minimizing its width when the outriggers are not in use, their operating mechanisms have tended to be somewhat complicated. Naturally, the complexity of these arrangements results in added fabrication and maintenance expense. Thus, an outrigger support arrangement of simplified construction which would still provide the necessary stabilization for a crane or similar piece of equipment, while being retractable to a stowed position so as to minimize the width of the piece of equipment between work operations, would be particularly suitable for use with equipment requiring stabilization during its use.